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Lack of sunshine in November

November 17, 2017

Lack of sunshine in November:

Many citizens around the state have remarked about the lack of sunshine so far this month. Indeed the data show emphatically the absence of sun has been quite pronounced. Mean cloudiness for the first half of the month ranges from 7 tenths to 8 tenths of the sky across most of the state and some climate stations have reported 9 days of complete cloud cover, while others have reported 8 days with fog.

If we examine historical climate statistics, November is traditionally the cloudiest month of the year, averaging nearly 6 tenths cloud cover of the sky on a daily basis. This is fully 25 to 35 percent more cloud cover than any other month. In terms of actual solar radiation (both direct and diffuse) the amount reaching the Minnesota landscape during November is approximately half of what it is in the month of July, and when compared with to the month with the next least amount of solar radiation (December) it is still about 8 percent less (a result of the low sun angle and shorter day length).

It is no wonder that November traditionally marks the annual onset of Seasonal Affective Disorder (SAD), sometimes called winter depression, winter blues, or seasonal depression. All of these terms refer to a mood disorder. The reduction in light is so pronounced in November across Minnesota, that many citizens turn to light therapy or other remedies to deal with it. In addition for some citizens the lack of light in November has a pronounced effect on their internal circadian rhythms so that the very long nights provoke earlier bedtimes or later awakening in the morning.

New Seasonal Climate Outlook:

The new seasonal climate outlooks were released by the NOAA Climate Prediction Center on Thursday, November 16th. They are weighted on the occurrence of a mild La Nina episode (cooler than normal waters in the equatorial Pacific Ocean prevailing throughout the Northern Hemisphere winter) and favor a cooler and wetter December-February period for Minnesota and the Dakotas. This by no means implies a winter similar to what we had four years ago (2013-2014), but obviously we might expect more below normal temperatures and perhaps more snowfall this winter across the state. It is much more uncertain if a cool, wet weather pattern will persist into the early spring months in 2018.

Weekly Weather Potpourri:

NOAA scientists report this week that portions of India and Pakistan have been plagued by persistent smog during November, fouling the air and make it quite unhealthy. Extreme levels of fine particulate matter showed up in some measurements taken there, producing a very poor air quality index.

A new study by scientists from the NASA-Jet Propulsion Laboratory finds that melting ice across the Northern Hemisphere, most significantly the Greenland Ice Sheet, will have variable effects on major coastal cities. The different regions of ice as they melt will translate to variable changes in sea level.

Congratulations to the clergy, faculty, and staff of St John’s University in Collegeville, MN for their recent award and recognition from the NOAA-National Weather Service. They have contributed 125 years of continuous daily weather observations to the central Minnesota climate data base, an enviable record which has allowed residents and state agencies to better understand climate behavior in that part of the state. Their dedication and outstanding service are justly commended.

The web site Carbon Brief announced a new online interactive map which examines the distribution of extreme weather events across the globe and according to case studies to what degree each of those weather events was related to climate change. The map covers almost every type of weather that has been studied by scientists.

MPR listener question:

My wife and I recently moved to the Twin Cities from Rome, Georgia where we used to always grill our turkey outside for Thanksgiving. She won’t let me do it if the temperature is below 40 degrees F because it takes too long. How often is the temperature on Thanksgiving below 40 degrees F on Thanksgiving in the Twin Cities?

Answer:

Let me put it this way, since 1872 a period of 145 years the Twin Cities have recorded a daytime temperature of 40 degrees F or higher only 28 percent of the time, most recently in 2015. That means that 72 percent of the time it is colder than 40 degrees F, so doing any outdoor grilling of turkey might be a bit of a challenge.

Twin Cities Almanac for November 17th:

The average MSP high temperature for this date is 40 degrees F (plus or minus 12 degrees F standard deviation), while the average low is 26 degrees F (plus or minus 10 degrees F standard deviation).

Average dew point for November 17th is 26°F; the maximum dew point on this date is 58°F in 1958; and the minimum dew point on this date is -14°F in 1959.

All-time state records for November 17th:

The all-time state high temperature for today's date is 76 degrees F at Canby (Yellow Medicine County) in 2001; the all-time state low for today's date is -19 degrees F at Hallock (Kittson County) in 1914. The all-time state record precipitation for this date is 3.21 inches at Tower (St Louis County) in 1996. Record snowfall is 15.0 inches at Roseau (Roseau County) in 1996.

Past Weather Features:

The coldest ever November 17th on a statewide basis was in 1914 as an Arctic High Pressure system rested over the state. It brought subzero temperature readings to 40 Minnesota communities, and even the daytime maximum temperature at Hallock never rose above 9°F.

Probably the warmest November 17th in state history was in 1953 when 35 communities in Minnesota reported afternoon highs of 70°F or greater. Even Grand Marais along the north shore of Lake Superior saw temperatures climb into the mid 50s F., and even the daytime maximum temperature at Hallock never rose above 9 degrees F.

A slow-moving winter storm plagued the state over November 15-17, 1996. This storm brought a mixture or rain, sleet, ice, and snow which resulted in widespread school closures and travel hazards. In southwestern Minnesota, thousands were without power for 5 days because accumulating ice brought down power lines. In northwestern Minnesota winds of 35-45 mph brought blizzard conditions, with heavy snow, and zero visibility. Many roads and highways were closed. Snow accumulations across the state ranged from 5 to 16 inches.

Outlook:

Colder than normal over the weekend, but generally sunnier skies as well. It will warm up to above normal temperatures on Monday, then cooler with a slight chance for snow on Tuesday. Moderating temperatures much of the rest of the week, and generally dry weather.